1994 chevy 3500 6.5TD

[troyporter]

Hi i am having a little trouble with my truck i am from good to some say great with trucks but having problems seeing whats wrong with this truck i put three different IP tryed 5 diff pmd replaced all the glow plugs replaced cps twice two new ops and the lift pump is working tryed a new computer still same thing starts hard sometimes very hard sometimes right up with minumal cranking. then when you start down the road it acts like it loads up you let it idle rough real rough missing and black smoke then it will clean up and run great go for a ride same thing. the code that i keep getting up is the crank sensor so i replaced again still same thing so i took the timming apart and the chain has about one inc of play in it so im going to replace them in the morning i was wondering if any body had any ideas on it. O and i went through the hole wiring harness found a bunch of bad wires fixed all them and have all the grounds up on the intake and six others motor to frame motor to body motor to battery on both sides of the truck have cold air filter and a staight three inc exhaust all the way back do you think that it could be the injectors and if it is would it miss all the time on that injector i crack them each when its running and the engine dies down on them all im getting stumped it sounds like a sensor to me it will run good untill it warms up. thanks for reading it let me know what you think. i will keep posted.

[john8662]

Which Crank sensor?

I've only had success with the OEM crank sensor. The Borg Warner replacement's all were Dead On Arrival.

J

[troyporter]

yea do you think that could be the problem ive tryed three of them and as soon as i put them in reset the computer and bam before its running its back on and that is the code you dont think that they would last for a min or so and if they are bad would the timing being off make the same thing read i took the timming apart and it looks like the crank gear and the cam gear are off does not look like it spun on the gears and the cam to the pump is dead on would it still run with the bottom side of the timming being off.

[DmaxMaverick]

What is your IP part number?

A 1" deflection of the timing chain may be enough to prevent the CKP and IP to locate, causing the code and poor running. A loose balancer or a shearing crank key (in progress) can cause a similar condition. Either one can eventually cause the other. These are less common issues, but possible. In any case, compensating the pump physical timing with a very sloppy timing chain, if it works, is only temporary, and masking the root problem. Continuing to run it with either condition will have an undesirable (catastrophic) result.

If it starts, the timing set is turning (not spun), and is not a temporary condition.

[john8662]

Which Brand? Borg Warner?

Seriously, I think the Borg Warner replacement Crank Sensor is a defect never tested in an actual engine before going to production. None of them work. Get an AC-Delco. I don't use Borg Warner's electrical products on a 6.5 any more because they've been 100% garbage.

[troyporter]

Well just got done with the timing chain and gears it started up hard still the check engine lights still on still reading crank sensor and still missing when it gets warmed up and it still stalling I am going to try some new injectors and try and find a better crank sensor if the bwd crank sensor are so bad then how do they get away with selling junk a got four know all junk at 50 a pop so the parts store just got me for more money does any one know were to find the better cps before i go and order another one and it show up being a junk one to thanks for your help.

[racer55]

Already posted GM dealer is the only place to get quality electronic parts for these trucks.
Rock Auto often stocks AC Delco and some parts stores will special order AC Delco.

Delphi might be alright also?

[john8662]

I don't know how BW offered their replacement CPS as a completly piece of junk that doesn't work. But, that was my experience.

I think they should all be recalled, especially reading what I've been reading you're going through.

12557046 is the PN for the CPS from the dealer/Rock Auto

[troyporter]

Ok now im lost i changed the crank sensor with a acdelco and that went away quick as soon as i hit the key there was no more check engine light i drove it around like one mile and it started to act up missing at idle real bad and going down the road so i pulled it back in and put the new injectors that came in it and it still missing the same as always bad lol. So at this point i have changed the ip,pmd,injectors,cps,ops,timing gears and chain, computer, batteries, alternator, went through the hole wiring harness and all the grounds are good triple checked new fuel filter drained the tank put fresh fuel in it checked all the injector lines for leakes im at a stand still not sure what else to change im going to start with the sensors on top the intake today the temp sensor air mixter and there is anther one not sure what it is going to look in the hanes to find out but was wondering if any one has any ideas of what this could be it has me stumped or is there any diesel macanics that are close to ludington mi to come and take a look at it.

[racer55]

Have you ever done a compression test?

Is the the OS electronic noise filter still in the OS harness?If so,remove it and plug the harness directly into the OS note results.

If there is some improvement but new symptoms some ferrite core from radio shack placed around each OS harness wire will have the same effect as the filter when it worked properly.

[DmaxMaverick]

What is the part number on your injection pump?

You have a 1994 HD truck, with an F code engine configuration and computer. Your truck has a UNIQUE injection pump series. All other years and models are interchangeable with other pumps. The 1994 HD/F is not. The incorrect pump will run, but poorly, perhaps like what you are seeing. Many shops, maybe most of them, make this mistake. Even the dealer gets it right about half the time.

[racer55]

The 94 3500 f engine requires in many cases a:
DS4831-5068 10225929 1994 HD C/K, G, and P3 Truck & Van * — —

Otherwise a prom from a 95 will need to be installed in the ECM,TDCO relearn will also be required after prom change.

Also I believe the 4 letter code of the ECM must be maintained between proms,an aftermarket ECM tune might be a good route to take to get everything matched up.

You don't yet have enough posts to receive private messages,so PM me for chip tuner recommendations.

[DmaxMaverick]

The 94 3500 f engine requires in many cases a:
DS4831-5068 10225929 1994 HD C/K, G, and P3 Truck & Van * — —

Otherwise a prom from a 95 will need to be installed in the ECM,TDCO relearn will also be required after prom change.

Also I believe the 4 letter code of the ECM must be maintained between proms,an aftermarket ECM tune might be a good route to take to get everything matched up.

You don't yet have enough posts to receive private messages,so PM me for chip tuner recommendations.

That's where I was going with it (a week ago). If it's a -5521 or -5067 pump, it could be as simple as that.

Only changing the prom to a 95 won't work. The prom has to match the ECM, and the 94 ECM is as unique as the pump. If a 95 ECM and prom is substituted, any of the DS4 pumps will work, including the -5068.

[troyporter]

well i went through the truck tonight traced all kinds of wires down put another injector pump on it off a running truck put a diffrent computer on it off a running truck and still no help i checked the return line and the fuel smelled like paint thinner so i drained the tank with the lift pump that is ran drect off the key put new in it and wala it fixed every thing it missed for a min and kleaned right up runs great thanks for all the advise i get to try it out tomorow to make sure but it sounds great but my alternator went out after one month of being new so i hope it all is good. i have one more question when my codes were coming up i had a 18 witch is a bad cam pulse error and a 54 and no were can i even find a code 54 in my chilton or on the net so was wondering what it is and if it will afect anything and what would make the truck go in to limp mode if you stand in it for a bit it goes in limp mode and will not come back till you shut it off and restart it what would cause that the egt to hot or what thanks for the help.

[troyporter]

Well i took my truck to work witch is a four hour drive it did good other than it went in to limp mood any thing over sixty five and would have no power it ran great just no power you stop shut it off and restart it it would be good till sixty five and i dont know if this matters but the cruise would stop working when it did it and i noticed that my wipers are not woking right on the relay setting and the sprayer does not work not sure if any of this makes since but would love to figure it out and fix it so i can pull my fithwheel home but in limp mood it will not pull it so i need to fix it the check engine light comes on and the only code i get is a 78 witch is the waste gate and bought a new one put in and checked all the lines does not leak and the canister is moving when i unplug it and plug it in so the pump is working any ideas any one greatly apreciated in advise.

[JohnC]

Bought a new what? 78 is wastegate solenoid, not wastegate.